When you perform both cardio and strength training in your routine, it is important to consider that cardio can interfere with muscle and strength development [1]. The timing at which you do cardio and strength training helps you minimize this "interference effect".
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If we look at the research, there seems to be a benefit to completely separating your cardio and strength workouts. A 2016 study found that separating your cardio and strength sessions by at least 6 hours results in improved strength gain in trained individuals [2]. A recent experimental study supports this by showing that muscle growth increases if cardio and strength training is performed on separate days [3].
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But I can imagine that not everyone has the time or energy to visit the gym on 2 separate occasions for your cardio and strength workout. If you perform cardio and strength training in the same session, prioritize what is more important to you [4]. If you would like to focus more on developing muscle size and strength, lift weights before doing cardio. For endurance athletes, the opposite applies.
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References:
1. Concurrent training: a meta-analysis examining interference of aerobic and resistance exercises. - PubMed - NCBI
2. Specific Training Effects of Concurrent Aerobic and Strength Exercises Depend on Recovery Duration. - PubMed - NCBI
3. Moderate Intensity Cycling Exercise after Upper Extremity Resistance Training Interferes Response to Muscle Hypertrophy but Not Strength Gains
4. Kang, J., & Ratamess, N. (2014). Which comes first? Resistance before aerobic exercise or vice versa?. ACSM's Health & Fitness Journal, 18(1), 9-14.